DKIM, which is an acronym for DomainKeys Identified Mail, is an email authentication system, which stops email addresses from being forged and email content from being tampered with. This is done by adding an electronic signature to each message sent from an email address under a given domain. The signature is issued based on a private cryptographic key that’s available on the outgoing SMTP server and it can be verified with a public key, which is available in the global DNS database. Thus, any message with altered content or a forged sender can be spotted by mail service providers. This method will enhance your online safety considerably and you’ll be sure that any message sent from a business collaborator, a banking institution, and so on, is legitimate. When you send out email messages, the receiver will also be sure that you are indeed the one who has sent them. Any email that appears to be counterfeit may either be flagged as such or may never be delivered to the recipient’s inbox, based on how the given provider has decided to treat such messages.